chore: zig test harness setup for parsing

src/parser_tests.zig

@@ -0,0 +1,110 @@
+const std = @import("std");
+const Ast = @import("./Ast.zig");
+
+test "parser: empty file" {
+    try testEqual(
+        \\
+    ,
+        \\File "<STDIN>"
+        \\
+        ,
+    );
+}
+
+test "parser: \"Hello World\"" {
+    try testEqual(
+        \\Hello, world!
+    ,
+        \\File "<STDIN>"
+        \\`--BlockStmt <line:1, line:1>
+        \\   `--ContentStmt <line:1, col:1:14>
+        \\      `--Content <col:1, col:14>
+        \\         `--StringLiteral `Hello, world!` <col:1, col:14>
+        \\
+        ,
+    );
+}
+
+test "parser: expression statements" {
+    try testEqual(
+        \\~ (-1 + 2) * 3 - -4
+    ,
+        \\File "<STDIN>"
+        \\`--BlockStmt <line:1, line:1>
+        \\   `--ExprStmt <line:1, col:3:20>
+        \\      `--SubtractExpr <col:4, col:20>
+        \\         |--MultiplyExpr <col:4, col:15>
+        \\         |  |--AddExpr <col:4, col:10>
+        \\         |  |  |--NegateExpr <col:4, col:6>
+        \\         |  |  |  `--NumberLiteral `1` <col:5, col:6>
+        \\         |  |  `--NumberLiteral `2` <col:9, col:10>
+        \\         |  `--NumberLiteral `3` <col:14, col:15>
+        \\         `--NegateExpr <col:18, col:20>
+        \\            `--NumberLiteral `4` <col:19, col:20>
+        \\
+        ,
+    );
+}
+
+test "parser: temporary variables" {
+    try testEqual(
+        \\~ temp a = 1 + 2 + 3
+        \\~ temp b = a + 1
+        \\{b}
+    ,
+        \\File "<STDIN>"
+        \\`--BlockStmt <line:1, line:3>
+        \\   |--TempDecl <line:1, col:3:21>
+        \\   |  |--Identifier `a` <col:8, col:9>
+        \\   |  `--AddExpr <col:12, col:21>
+        \\   |     |--AddExpr <col:12, col:17>
+        \\   |     |  |--NumberLiteral `1` <col:12, col:13>
+        \\   |     |  `--NumberLiteral `2` <col:16, col:17>
+        \\   |     `--NumberLiteral `3` <col:20, col:21>
+        \\   |--TempDecl <line:2, col:3:17>
+        \\   |  |--Identifier `b` <col:8, col:9>
+        \\   |  `--AddExpr <col:12, col:17>
+        \\   |     |--Identifier `a` <col:12, col:13>
+        \\   |     `--NumberLiteral `1` <col:16, col:17>
+        \\   `--ContentStmt <line:3, col:1:4>
+        \\      `--Content <col:1, col:4>
+        \\         `--InlineLogicExpr <col:1, col:4>
+        \\            `--Identifier `b` <col:2, col:3>
+        \\
+        ,
+    );
+}
+
+test "parser: temporary assignment" {
+    try testEqual(
+        \\~ temp a = 123
+        \\~ a = 321
+    ,
+        \\File "<STDIN>"
+        \\`--BlockStmt <line:1, line:2>
+        \\   |--TempDecl <line:1, col:3:15>
+        \\   |  |--Identifier `a` <col:8, col:9>
+        \\   |  `--NumberLiteral `123` <col:12, col:15>
+        \\   `--AssignStmt <line:2, col:3:10>
+        \\      |--Identifier `a` <col:3, col:4>
+        \\      `--NumberLiteral `321` <col:7, col:10>
+        \\
+        ,
+    );
+}
+
+fn testEqual(source_bytes: [:0]const u8, expected_ast: []const u8) !void {
+    const gpa = std.testing.allocator;
+    var arena_allocator = std.heap.ArenaAllocator.init(gpa);
+    defer arena_allocator.deinit();
+    const arena = arena_allocator.allocator();
+
+    var allocating = std.io.Writer.Allocating.init(gpa);
+    defer allocating.deinit();
+
+    const ast = try Ast.parse(gpa, arena, source_bytes, "<STDIN>", 0);
+    try ast.render(gpa, &allocating.writer, .{
+        .use_color = false,
+    });
+    return std.testing.expectEqualSlices(u8, expected_ast, allocating.written());
+}

src/root.zig

@@ -6,5 +6,6 @@ test {
     _ = tokenizer;
     _ = Ast;
     _ = Story;
+    _ = @import("parser_tests.zig");
     _ = @import("Story/runtime_tests.zig");
 }